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Categories: Paleontology: Climate, Space: Astrophysics
Published Hubble directly measures mass of a lone white dwarf
(via sciencedaily.com) Astronomers have directly measured the mass of a single, isolated white dwarf -- the surviving core of a burned-out, Sun-like star. Researchers found that the white dwarf is 56 percent the mass of our Sun. This agrees with earlier theoretical predictions of the white dwarf's mass and corroborates current theories of how white dwarfs evolve as the end product of a typical star's evolution. The unique observation yields insights into theories of the structure and composition of white dwarfs.
Published Astronomers uncover a one-in-ten-billion binary star system: Kilonova progenitor system
(via sciencedaily.com) Astronomers using data from the SMARTS 1.5-meter Telescope at the Cerro Tololo Inter-American Observatory (CTIO), have made the first confirmed detection of a star system that will one day form a kilonova -- the ultra-powerful, gold-producing explosion created by merging neutron stars. These systems are so phenomenally rare that only about 10 such systems are thought to exist in the entire Milky Way.
Published The bubbling universe: A previously unknown phase transition in the early universe
(via sciencedaily.com) What happened shortly after the universe was born in the Big Bang and began to expand? Bubbles occurred and a previously unknown phase transition happened, according to particle physicists.
Published Scientists release newly accurate map of all the matter in the universe
(via sciencedaily.com) A group of scientists have released one of the most precise measurements ever made of how matter is distributed across the universe today.
Published Monitoring an 'anti-greenhouse' gas: Dimethyl sulfide in Arctic air
(via sciencedaily.com) Data stored in ice cores dating back 55 years bring new insight into atmospheric levels of a molecule that can significantly affect weather and climate.
Published Starry tail tells the tale of dwarf galaxy evolution
(via sciencedaily.com) A giant diffuse tail of stars has been discovered emanating from a large, faint dwarf galaxy. The presence of a tail indicates that the galaxy has experienced recent interaction with another galaxy. This is an important clue for understanding how so called 'ultra-diffuse' galaxies are formed.
Published Mercury helps to detail Earth's most massive extinction event
(via sciencedaily.com) Scientists are working to understand the cause and how the events of the LPME unfolded by focusing on mercury from Siberian volcanoes that ended up in sediments in Australia and South Africa.
Published Solar System formed from 'poorly mixed cake batter,' isotope research shows
(via sciencedaily.com) Earth's potassium arrived by meteoritic delivery service finds new research led by Earth and planetary scientists. Their work shows that some primitive meteorites contain a different mix of potassium isotopes than those found in other, more-chemically processed meteorites. These results can help elucidate the processes that shaped our Solar System and determined the composition of its planets.
Published NASA's Fermi detects first gamma-ray eclipses from 'spider' star systems
(via sciencedaily.com) Scientists have discovered the first gamma-ray eclipses from a special type of binary star system using data from NASA's Fermi Gamma-ray Space Telescope. These so-called spider systems each contain a pulsar -- the superdense, rapidly rotating remains of a star that exploded in a supernova -- that slowly erodes its companion.
Published Kill dates for re-exposed black mosses
(via sciencedaily.com) Scientists have used radiocarbon ages (kill dates) of previously ice-entombed dead black mosses to reveal that glaciers advanced during three distinct phases in the northern Antarctic Peninsula over the past 1,500 years.
Published What crocodile DNA reveals about the Ice Age
(via sciencedaily.com) What drives crocodile evolution? Is climate a major factor or changes in sea levels? Determined to find answers to these questions, researchers discovered that while changing temperatures and rainfall had little impact on the crocodiles' gene flow over the past three million years, changes to sea levels during the Ice Age had a different effect.
Published Were galaxies much different in the early universe?
(via sciencedaily.com) The most sensitive telescope now searching for radio signals from cosmic dawn, an era around 200 million years after the Big Bang when stars ignited, has doubled its sensitivity, a new paper reports. While not yet detecting this radiation -- the redshifted 21-centimeter line -- they have put new limits on the elemental composition of galaxies during the Epoch of Reionization. Early galaxies seem to be low in metals, fitting the most popular theory of cosmic evolution.
Published How a 3 cm glass sphere could help scientists understand space weather
(via sciencedaily.com) Space weather can interfere with spaceflight and the operation of satellites, but the phenomenon is very difficult to study on Earth because of the difference in gravity. Researchers effectively reproduced the type of gravity that exists on or near stars and other planets inside of a glass sphere measuring 3 centimeters in diameter, or about 1.2 inches. The achievement could help scientists overcome the limiting role of gravity in experiments that are intended to model conditions in stars and other planets.
Published Darkest view ever of interstellar ice
(via sciencedaily.com) Original source Astronomers used observations from the James Webb Space Telescope (JWST) to achieve the darkest ever view of a dense interstellar cloud. These observations have revealed the composition of a virtual treasure chest of ices from the early universe, providing new insights into the chemical processes of one of the coldest, darkest places in the universe as well as the origins of the molecules that make up planetary atmospheres.
Published Stars disappear before our eyes
(via sciencedaily.com) Original source A startling analysis from Globe at Night -- a citizen science program -- concludes that stars are disappearing from human sight at an astonishing rate. The study finds that, to human eyes, artificial lighting has dulled the night sky more rapidly than indicated by satellite measurements.
Published Massive fuel-hungry black holes feed off intergalactic gas
(via sciencedaily.com) Research has revealed how supermassive black holes (SMBHs) are feeding off gas clouds which reach them by traveling hundreds of thousands of light years from one galaxy to another.
Published Malformed seashells, ancient sediment provide clues about Earth's past
(via sciencedaily.com) Shrunken seashells and unusually dark sediment cores have helped geoscientists better understand the chronology and character of events that led to Ocean Anoxic Event 2, nearly 100 million years ago.
Published In the Neanderthal site of Combe-Grenal, France, hunting strategies were unaffected by changing climate
(via sciencedaily.com) Neanderthals in Combe-Grenal (France) preferred to hunt in open environments, and their hunting strategies did not alter during periods of climatic change, according to a new study.
Published Billions of celestial objects revealed in gargantuan survey of the Milky Way
(via sciencedaily.com) Original source Astronomers have released a gargantuan survey of the galactic plane of the Milky Way. The new dataset contains a staggering 3.32 billion celestial objects -- arguably the largest such catalog so far. The data for this unprecedented survey were taken with the Dark Energy Camera.
Published How was the solar system formed? The Ryugu asteroid is helping us learn
(via sciencedaily.com) Original source Our solar system is estimated to be about 4.57 billion years old. Previous analyses of ancient meteorites have shown that minerals were created through chemical reactions with water as far back as 4.5 billion years ago. New findings from the Ryugu asteroid samples indicate that carbonates were forming from water-rock reactions several million years earlier, even closer to the solar system's beginnings.